The people most likely to threaten your borders are also the people you’re most likely to share culture and genes with. So minor differences in language, cultu

The people most likely to threaten your borders are also the people you’re most likely to share culture and genes with. So minor differences in language, culture, and geography become important signs of essential distinction from your historical enemy. Freud called this the “narcissism of small differences” (https://en.m.wikipedia.org/wiki/Narcissism_of_small_differences https://en.m.wikipedia.org/wiki/Narcissism_of_small_differen...).